The Best Double Sleeping Bag for Car-Camping Couples

After recruiting nine sleeping-bag-testing couples to try out a total of six double bags on three group camping trips, we reached the conclusion that the Big Agnes Dream Island is the most comfortable and functional double sleeping bag for casual car campers. We liked the comfort—and quiet—of the Dream Island’s sheetlike brushed-cotton lining better than the lining on any other bag. The bag’s integrated sleeping-pad pocket stopped us from sliding in the night—a common problem when two bodies fight each other and possibly gravity to stay put atop a slippery sandwich of tent, pad, and bag. Finally, unlike some of the other bags we tested, the Dream Island has a reasonable weight and heft that won’t fill half your trunk or leave you cursing as you struggle to stuff it back in its sack.

Why would you even want a double bag? No, it’s not high on the list of outdoor essentials. But after spending a few months doubling up on a regular basis, we’re convinced that it’s one of the appealing extravagances of car camping: A big bag can keep you cozy through shared body heat, give you more room to stretch out, and facilitate romance (another scientifically proven way to make your bag hotter). It can also be less expensive than buying two separate sleeping bags of similar quality. But the best reason to get a double sack may be that it makes car camping more like sleeping in your own bed at home—which just may help the more camping-gung-ho member of a couple convince the other to get out into the wild a little more often.

The Big Agnes Dream Island is spacious, warm, and comfortable, with a built-in sleeping-pad sleeve that solves a problem it had never occurred to us to try to solve: the annoyance of bag and pad getting misaligned in the middle of the night. The pad, bought separately, replaces insulation on the bottom half of the bag, making the Big Agnes, which is rated to 15 degrees Fahrenheit, extra warm for its packed size.

The Frontcountry Bed’s zipper-free design feels more like sleeping with your honey at home; one partner can push the covers off while the other pulls them up—no zipping required. Like the Big Agnes bag, the Frontcountry, rated to 27 degrees Fahrenheit, has integrated pockets for sleeping pads (Duo model) or an air mattress (Queen model).

Why you should trust us

I have evaluated gear for magazines including Wired, Popular Science, and National Geographic Adventure, where I was a senior editor. I’m a longtime hiker and camper, and embraced the transition from backpacking to car camping—which included buying a double bag—after my first son was born five and a half years ago. I now have a garage full of dusty backpacking gear, a hot-sleeping husband, and two cuddly little boys who like to wake up at least a half-hour before the crack of dawn and snuggle into bed with Mom and Dad.

In addition to drawing on personal experience, we scoured online reviews, polled frequent-car-camping families about their sleeping bag preferences, and recruited eight other California couples to test bags on weekend camping trips. Our first trip was to the high desert of Joshua Tree National Park, where we encountered early-February lows in the mid 30s. In March, we headed for the sycamore groves of Point Mugu State Park on the Pacific coast, where wet and blustery weather paired with mild temperatures in the 50s and 60s. We left our hats at home in late April, when a trip to dry and woodsy Wheeler Gorge near Ojai, California, saw nighttime lows in the high 50s.

We started by spending four hours evaluating the online reviews of all the double bags we could find. We visited company sites to look at the specs on different bags, comparing materials, shapes, features, and price. We quickly noticed that synthetic bags are far more common than down ones, and that all the down bags available are hundreds of dollars more expensive than comparable synthetics. Though synthetic double bags range from about $100 on the low end to a high-end price of about $300, the least-expensive down bags cost about $450.

Down packs smaller and is warmer for its weight than synthetic (more on the science of sleeping bag design and the benefits of down vs. synthetic here). Though we know many dedicated campers and backpackers prefer the feel and warmth-to-weight ratio of down, especially if they’re lugging it in a backpack, we decided to limit our comparison to the more reasonably priced synthetic bags, which we think are a much more common and practical choice for car camping. We hope to review down doubles in the future. In the meantime, if you prefer down, the companies that make our top two picks—Big Agnes and Sierra Designs—make similar down doubles primarily intended for backcountry camping.

We noticed that though higher-end brands sometimes make double bags with a mummyish shape, meaning a bottom that’s narrower than the top, the more common shape for double bags is a straight rectangle. And, usually, you can zip apart the bottoms and tops of those rectangular bags to create two separate bags, a feature that obviously adds versatility to a purchase. It’s worth noting that quite a few single sleeping bags can be zipped together with an identical bag to created an ad-hoc double bag. For this story, we focused only on purpose-built double bags.

A pile of bags, some with loftier ambitions than others. Top to bottom: Big Agnes, Sierra Designs, Alps Mountaineering, Teton Sports, Slumberjack, The North Face. Photo: Jeremy Pavia

We wanted a three-season bag warm enough for fall and spring camping in most areas of the country. Sleeping bag ratings state the lowest temperature at which the average person can expect to sleep comfortably (that’s using a sleeping pad and beanie and wearing long johns). Of course, you might not be average. If you tend to sleep cold, you may want to choose a warmer bag. We think a sleeping bag with a rating no higher than 30 degrees Fahrenheit will be comfortable for most people for three-season trips. You could buy very inexpensive double bags with a higher rating, but they may leave you shivering on a chilly night. (Note that though most high-quality adult bags now use a standardized “EN” rating validated by a third-party scientific group, this test is not available for double bags.)

Then we started sleeping. We spent a couple nights in each bag on top of our own bed, letting our kids snuggle in with us in the early mornings, as they typically do at home or at a campsite. We quickly developed preferences for which bag to grab for weekend naps with our one-year-old, or midafternoon snoozes during a busy workday. We took the bags on three group camping trips. The first was an early-February trip to Indian Cove Campground in Joshua Tree National Park, where nighttime temperatures dipped into the mid-30s. The second was a damp and windy March trip to the oceanside Sycamore Canyon Campground at Point Mugu State Park in Oxnard, California. The third trip brought us to woodsy Wheeler Gorge near Ojai, California, where we experienced mild nighttime lows in the 50s. We distributed our double bags to couples of varying heights, sizes, and sleeping preferences. We polled each couple on their experience with the bags they tested, asking for feedback on features they loved and loathed.

Temp rating

Dimensions (width by length)

Stuff size

Pack
weight

Converts to two bags

Big Agnes Dream Island

15°F

65″ by 73″ (84″ with hood)

13″ by 23″

9 lbs., 7 oz.

No

Sierra Designs Frontcountry Bed Duo

27°F

53″ by 84″
(including hood)

13″ by 21″

7 lbs., 12 oz.

No

Alps Mountaineering Twin Peak 20°

20°F

68″ by 78″

17″ by
27″

11 lbs., 9 oz.

Yes

The North Face Dolomite Double 20/-7

20°F

59″ by 82″

12″ by 24″

8 lbs., 14 oz.

Yes

Slumberjack Bonnie & Clyde

30°F/
40°F

67″ by 75″

16″ by 34″

9 lbs., 8 oz.

Yes

Teton Sports Mammoth 0°F

0°F

59″ by 79″ (91″ with hood)

15.5″ by 28″

16.5 lbs.

No

We found inconsistencies with the way companies measure bags, so we pulled out our own tape measure. Our measured dimensions list the width of the bag at the shoulders, then the length of the bag from chin to foot (we also listed the length with hood on those bags that include one). Only the Big Agnes bag is tapered, with a bottom that is significantly narrower than the top. Our weight measurement is of packed weight (the bag inside its included stuff sack).

After developing a rough sense of our favorite and least-favorite bags on our group trips, we spent more time at home comparing how easily the sacks zipped and unzipped, inspecting their real-world weight and size against published specs, and evaluating how much physical struggle and agitation was associated with inserting them into and extracting them from their included stuff sacks.

Everybody has their own preferred kind of stuffing. Left to right: The North Face, Big Agnes, Sierra Designs, Alps Mountaineering, Teton Sports, Slumberjack. Photo: Jeremy Pavia

In the process, we reached the conclusion that there’s no single best bag for everyone. The size and shape of a couple—and their car—might put priority on choosing a bag that packs small (the Dream Island will require half the trunk space of a bag like the Bonnie & Clyde) or sleeps big. We found that though every company publishes size and weight specs on its bags, they’re not all measuring the same thing. We took our own side-by-side measurements for more accurate comparison (see chart above). The Teton Sports Mammoth is the longest we tested; the Alps Mountaineering Twin Peak is the widest.

Our pick

A sleeping bag with built-in pockets for pads and bedding is a great idea. Photo: Jeremy Pavia

The Big Agnes Dream Island is the most comfortable double bag for car-camping couples.

The Big Agnes Dream Island comes closer to feeling like a real bed than any other double bag we tested. A built-in sleeping-pad pocket eliminates the middle-of-the-night bunching and sliding we’ve experienced with other bags (the pad is sold separately). The Dream Island is also unusually lofty and comfortable—more like sleeping with a big, soft quilt draped over you than bunking up in a typical sleeping bag.

Sleeping next to each other in single bags is like using a bunk bed on your honeymoon. There’s a better way. Photo: Jeremy Pavia

Though the Dream Island’s outer shell is ripstop nylon, the bag’s inner lining is made of a soft cotton-polyester blend that feels like a good-quality bedsheet. We loved the material for its softness, as well as for the fact that it eliminated the constant swishing noises that inevitably accompany a night in a nylon- or polyester-lined bag. Of course, when there are two or more bodies shifting around, there’s twice as much sound. On a night when a teething baby was retrieved from his crib to be cuddled and breastfed in the bag, Dad was able to remain asleep even with constant shifting of Mom and babe. When a half-dozen bags were piled in our home office, we found this became our go-to bag for midafternoon catnaps (our actual cat liked it too).

The rare Cornish rex feline breed is too delicate constitutionally to venture into the out-of-doors, but the bedlike nature of modern sleeping bags makes for a fine interior repose. Photo: Kalee Thompson

The Dream Island uses 75 ounces of Thermolite-brand synthetic insulation. It has a generous 136-inch circumference at the shoulders, then tapers modestly to 121 inches at the hips and 110 inches at the foot, where it has a roomy box cut. We liked thoughtful features like the small strip of “no-draft” fabric that snaps between the heads of its two inhabitants, allowing them to better seal themselves in and stay warmer on cold nights. The drawstring at the hood cinches in four spots, allowing each member of a couple to adjust the hood precisely to their own preferences.

The thing we love the most about the Big Agnes is the built-in sleeping pad sleeve, which works best with a double-size pad like the Big Agnes Double Z, above. Photo: Jeremy Pavia

Because the Dream Island sandwiches sleepers securely between pad and bag, there’s no slipping and sliding.

The most distinctive feature of the Big Agnes bag is its integrated sleeping-pad sleeve that allows it to dispense with insulation in the bottom half of the bag. At first, we were skeptical of this design, which seemed like it might be too fussy or not versatile enough. But after three weekend car-camping trips and a half-dozen nights with the bag layered on our own bed at home, we’re convinced of the superiority of this design. The Big Agnes system addresses a problem it had never occurred to us to try to solve: The annoying tendency of a sleeping bag to slide off or become otherwise akilter from a sleeping pad in the middle of the night. Previous camping trips in a double bag placed on top of an Aerobed-type mattress had led us to conclude that this problem becomes more acute when you’re two to a bag. Nylon or polyester bags can be slippery atop also-slippery air mattresses, with a tendency to either shimmy down the mattress or flop off one side. The problem is exaggerated if you pitch your tent on anything but perfectly flat ground. But because the Dream Island sandwiches sleepers securely between pad and bag, there’s no slipping and sliding; instead you get a better shot at a restful sleep.

The inflation valve is left exposed, near your head, so you can add a little support if you need it. Photo: Jeremy Pavia

The Dream Island’s sleeve fits one of Big Agnes’s 50 by 78 inch double air mattresses (we used the Insulated Double Z) or two standard 25 by 78 inch pads, like Big Agnes’s Air Core or Hinman models. Many companies make car-camping pads with these larger-than-average dimensions, and any of them will fit the Dream Island just fine. Though you could also use two smaller 20 by 72 inch pads—a common size for Therm-a-Rest-type camping pads—they’ll leave several extra inches on all sides of the Big Agnes’s sleeve. If you’re going to be investing in a high-quality double bag like this one, we recommend pairing it with a double pad that fits perfectly.

Pillow covers included. Photo: Jeremy Pavia

At home, we occasionally slept inside this bag directly on top of a king-size bed, and didn’t notice the lack of insulation underneath us. That said, we don’t think it would make sense to buy this bag if you’re not intending to use the integrated sleeve; if you’re not planning to buy into the Big Agnes system, either of our alternate picks become stronger options.

Only the new tricolor bag has the cotton lining we love.

Though a couple of our tested bags might take up a third of the space in a small trunk and weigh close to 12 pounds, the Dream Island packs down to a relatively compact 13 by 23 inches when in its stuff sack; it weighs 9 pounds, 7 ounces. It’s also the only bag we found that comes with a separate mesh storage bag, making it easy to store correctly for maximum loft protection.

The Dream Island is the biggest and second-least-expensive bag in Big Agnes’s line of double bags, which includes down bags like the $450 King Solomon and the $650 Saddle Mountain, which at 3 pounds, 13 ounces is made for serious backpacking couples. The Big Agnes updated the Dream Island for spring 2016, and though the earlier version of the bag got rave reviews (and is now on sale at Amazon), only the new tricolor bag has the cotton lining we love. Other new-for-2016 features include a “pillow barn” that allows you to tuck your pillow into the sheetlike fabric, and corner hand pockets on the comforter so you can “snuggle that top layer of the bag in around your neck,” Big Agnes senior marketing specialist Katie Hughes told us. The company is planning to add some of the Dream Island’s new features to the other bags in the line for spring 2017, she said.

Backpacker recommends the Big Agnes bags as a good option for newlyweds; REI customers liked the previous version of the Dream Island, with one writing that he and his wife “both agreed we’d never had a more comfortable [night”s] sleep while camping.” Stephen Regenold of Gear Junkie called an older Dream Island “luxurious” and said it’s worth the cash: “If you’re the type who totes along a camp-stove espresso maker, Lexan wine glasses and leg-rest-equipped camp chairs, then the Big Agnes setup will be up your alley,” he wrote in 2008. (The newly redesigned Dream Island has so far accumulated just a couple of online reviews.)

Flaws but not dealbreakers

Though the bag is rated to 15 degrees Fahrenheit, it left me slightly chilly on a February night in the high desert of Joshua Tree National Park (low: 36 degrees). Admittedly, I sleep cold, and usually reach for a decade-old down bag rated to 0 degrees whenever there’s a chance of temperatures dipping into the 30s. Most of the other couples we camped with that weekend were also colder than they would have liked inside rival double bags. Unfortunately, it is difficult to evaluate the warmth of the bags objectively because none of them adhere to EN standards, protocols in which researchers establish the warmth of a bag through standardized laboratory testing.

The brushed-cotton lining also makes the bag more difficult to clean than all-nylon or polyester models. Though you can fairly easily give a polyester bag a quick sponge bath inside and out, the Dream Island required an unwieldy scrub in the bathtub after my infant son spit up inside it.

More like a bedspread

A unique shape and pockets for pillows make the Sierra Designs bag more like a comfy comforter. Photo: Jeremy Pavia

Sierra Designs’ Frontcountry and Backcountry beds are leaders in a trend toward sleeping bags that are more like, well, regular beds. The line dispenses with zippers altogether, instead making use of a comforter shaped like an oversized tongue. With the blanket section folded down, cuddling up in the bed looks a lot like climbing into a supersize slipper. With the blanket section pulled up, the bed offers far more flexibility than the typical sleeping bag. Snoozers can stick a knee or elbow out the side for a little cool air, tuck an arm in the built-in pocket at the comforter’s edge and stretch the blanket over their head, or pop their feet out of the ingenious draft-free pocket at the bottom of the bag, a feature we noticed men appreciated most as they were frequently sleeping with wives or girlfriends who wanted as much tuck-in—and heat—as possible.

Just like at home, temperature regulation and position are sources of conflict when you sleep with somebody. And just like at home, the Sierra Designs Frontcountry Bed Duo lets you roll around and find your personal comfort zone. Photo: Jeremy Pavia

The synthetic Frontcountry Beds, rated to 27 degrees Fahrenheit, are new for spring 2016, and come in Duo (double) and Queen versions, with current list prices ($200 and $230, respectively) far less expensive than those of Sierra Designs’s equivalent down bags. The Frontcountry Beds are also heavier and pack bigger than the down Backcountry Beds. As the name implies, these are beds made for car camping.

We slept in the Frontcountry Bed Duo at home and took it to the woods. Though we loved the overall design, which allows a couple with very different sleeping-temperature preferences to bed up together in comfort, we disliked the typical polyester sleeping-bag lining when compared with the brushed cotton of the Big Agnes. Once we were used to sleeping in a bag without the swish, we found it extra annoying when we encountered it again. But we think that’s probably the type of thing that bugs some people but others not at all. If soft polyester feels just fine to you, we think you’ll love everything about this bag.

A note: Though we tested the smaller Duo, we’d recommend people consider spending a little extra for the larger Queen bed, especially if there’s a likelihood of a kid crawling in before sunrise. Although the Duo had the second-smallest dimensions of all the bags we tested, the Queen is much roomier with an extra 10 inches of width compared with the Duo.

A standard polyester liner, a little less comfy compared to the Big Agnes. Photo: Jeremy Pavia

Like the Big Agnes bag—but unlike every other bag we tested—the Frontcountry Beds have built-in sleeping-pad sleeves. We love these for the same reasons we love the ones on the Big Agnes: No losing contact with your pad during a restless night. Note that though the Big Agnes bag doesn’t have padding on the bottom of the bag, the Frontcountry Beds do. The Big Agnes bag is also ideally paired with a double sleeping pad (though two singles will work, too); the Frontcountry Duo is designed to take two separate pads of either of the most common sleeping-pad sizes, 78 by 20 inches or 78 by 25 inches, and up to 3 inches thick (it’ll also work fine with a shorter 72-inch pad). The Frontcountry Bed Queen, in contrast, has a pad attachment that’s more like a fitted sheet, with a shock-cord bungee along the perimeter. It’ll fit a standard 80 by 60 inch queen Aerobed-type air mattress up to 9 inches high, or a camping-specific pad of the same dimensions. Some people will likely want to choose between the Duo and the Queen based on what type of sleeping pads they already own or prefer to buy.

Alps Mountaineering’s large and soft Twin Peak 20° offers the best balance of features and price among several cheaper-but-bulkier bags we tested.

The Alps Mountaineering Twin Peak 20° is bulky and lacks the built-in sleeping-pad pocket we’ve come to love. Still, it costs less than any of the other double bags we tested and has a couple nice features that allow it to edge ahead of other less-expensive options. First, we liked the bag’s sheetlike lining, which reminded us of the interior we loved on our favorite, the Big Agnes Dream Island. Second, the bag has sandwich-bag-size zippered pockets on both sides, ideal for the phones and headlamps that are so easy to misplace in a dark and perhaps cluttered tent. It was the only bag we tested that had this practical feature.

Storage for your phone or headlamp. Photo: Jeremy Pavia

At 80 inches long and 68 inches wide, the Twin Peak is slightly longer than the Slumberjack Bonnie & Clyde and wider than the The North Face Dolomite Double 20/-7, two other highly rated bags we tested. Though undeniably huge, it packs smaller than either the Slumberjack or the Teton Sports Mammoth, and unlike the Mammoth, it doesn’t require a mammoth effort to stuff it back inside its sack. In short, it’s a comfy bag for a great price that will keep a couple or small family cozy at camp. Two kids who hadn’t both slept through the night in a month managed to pass out for 10 hours straight on the living room floor once they were tucked into this bag. Cause and effect? Maybe not. Warm and comfortable? Definitely.

The competition

The competition, from left to right: Teton Sports, The North Face, Slumberjack. Photo: Jeremy Pavia

The North Face Dolomite Double 20/-7
Our testers liked the simple yet functional The North Face Dolomite Double 20/-7, which gets glowing reviews from users on the company’s site, REI’s site, and Backcountry. At 8 pounds, 14 ounces, it’s lighter and packs down smaller than most of the other bags we tested, and—like the Big Agnes bag—it has snaps at the collar that can help keep warm air in and cold air out on a chilly night. You can easily zip it apart to make two separate (though very narrow) bags—an option two of our testers chose on night two in Joshua Tree National Park after one camper accused her husband of turning the double bag into a stinky Dutch oven. (We can’t blame the bag, nor will we link to a definition of the term for the uninitiated. Give thanks you don’t know.)

Our main criticism of the Dolomite was one we probably wouldn’t have had if we hadn’t slept in so many competitors: the slipperiness and constant swishing sound of a bag that’s polyester inside and out. Almost all of our testers preferred a more sheetlike lining when presented with the choice. (A counterpoint: A polyester or nylon lining is easier to clean with a quick sponge bath.) The Dolomite is also noticeably less lofty that the other bags we tested, and with a current price tag of $160 or so, it’s more expensive than other rectangular doubles.

Like the Slumberjack and Alps Mountaineering bags, the Dolomite is sized to fit people up at 6 feet tall. Unlike the other two bags, it comes in a long version that fits people up to 6 feet 6 inches.

Slumberjack Bonnie & Clyde
The Slumberjack Bonnie & Clyde is a good bag for a couple who like the feel of flannel and who might be sleeping with a kid or two tucked between them. At 68 inches wide, it’s about six inches wider than The North Face’s Dolomite and a couple inches wider than the Alps Mountaineering Twin Peak. The Slumberjack is more lofty than either of those bags, at least when new. But it’s also a little shorter, making it a poor choice for tall people. Though the company says the bag fits individuals up to 6 feet tall comfortably, in real life it’s a couple inches shorter than other bags that make that identical claim.

At 9 pounds, 8 ounces, the Bonnie & Clyde isn’t heavier than its direct competitors. But when stuffed in its duffel-like bag it remains huge—taking up more space when packed than any other bag we tested. We also found that its zippers tend to get stuck more than those on competing bags, something that Amazon reviewers have also noted. And though we haven’t been cold in this bag on high-30s nights, its temperature rating is higher than any other we tested for this story.

It comes with two worthless doll-size pillows. Bring your own favorite pillow from home; you are car camping, after all.

Teton Sports Mammoth 0°F
Weighing in at 16.5 pounds with a length of 94 inches (including the hood), Teton Sports’ Mammoth 0°F bag truly is enormous. The version we tested was rated to 0 degrees, warmer than any other we tried (the bag also comes in a 20° version, which usually costs about $10 less). It’s similar to our favorite budget bag, Alps Mountaineering’s Twin Peak 20°, but with a few key differences. First, though the Alps bag (as well as The North Face’s bag and the Slumberjack) has bottoms and tops that’ll line up at the top of your mattress, the Mammoth is designed more like our favorite Big Agnes and Sierra Designs bags, with a mummy-style hood to rest your head on that extends a good foot above the top of the top cover. A hood is cozy, but it also means that you lose the versatility of being able to unzip the bag into two separate single bags, which The North Face’s bag, the Slumberjack, and the Alps bag all do.

Our testers liked the Mammoth’s supersoft brushed-poly flannel lining and its roomy cut, though the couple who used the bag on our camping trip to Joshua Tree National Park were agitated by the cinch cord, which falls at the neck in a flap of fabric that interrupts the bag’s otherwise smooth lining. The company boasts that the bag is the right size to fit a couple and a child, or—slightly amusingly—four children sleeping together. Amelia Mayer, blogger at Tales of a Mountain Mama, successfully used it to introduce her kids to winter camping; outdoor-industry dad Tim Miner discovered that the bag got his kids to sack down earlier; and hundreds of Amazon reviewers love it, including T. L. Wheeler, who writes: “My husband is 6’6″ and he is able to fit in it deep enough to cover completely up. It is roomy enough for us both to move and sleep very comfortably. It is warm, and I mean WARM!!” One of our testing couples, a 6-foot-6 man and a 5-foot-10 woman, slept in the bag at Wheeler Gorge Campground near Ojai, California, in April and found it plenty big and warm, though they had a hard time keeping it on their side-by-side sleeping pads. After a poor night’s rest they declared the effort required to get the bag back in the way-too-tight sack “absolutely not worth it.”

There’s no doubt: It takes a near-Herculean effort to wrestle this bag back into its carry bag. Enough users have complained about it that the company actually posted a video proving that it can be done. Mission accomplished? Yeah, but not without some muscle and sweat—and more under-the-breath expletives than the typical mom might want her four now-wide-awake kids to overhear.

Care, use, and maintenance

Cleaning: Avoid the wear and tear of machine washing when spot cleaning will do. We slung bags over the clothesline and simply wiped them down with a wet cloth following our particularly sticky and dusty trip to Joshua Tree. Most outdoor companies recommend that you wash sleeping bags in the bathtub, or in front-load washers with cold water and gentle soaps (REI recommends these). Double bags that unzip into two can be washed in two loads; a double bag that doesn’t separate is most likely going to call for a trip to the closest laundromat with a supersize washer. More sleeping-bag care tips are available from REI, Big Agnes, and Backpacker magazine.

Storage: You should store a sleeping bag out of its stuff sack. Of the bags we looked at, only the Big Agnes ones come with two storage bags, a compression sack for a crowded car, and a larger, looser mesh bag for long-term storage. As with any camping gear, avoid mildew by ensuring a sleeping bag is completely dry before returning it to its bag. Big Agnes’s FAQ includes a discussion of optimum storage.

Fighting Cold: Though a bag with a lower rating should, in theory, keep you warmer, what that bag is placed on matters, too. On cold nights, the more insulation between your body and the heat-sucking earth, the better. We’ve seen car campers conk out on foot-high Aerobeds, bulky cotton futons, exercise mats, strips of cheap foam, or simply an old quilt. Anything is better than nothing in terms of comfort, but if you’re concerned about warmth, look for a dedicated sleeping pad with an R value of at least 2.5 for three-season camping (a foot-high, big-box-store air mattress has an R value of about 1, meaning it is not a great choice for warmth).

A couple more fairly obvious tips: Wear a hat and warm socks and long johns to bed. Bring a hot-water bottle from home or make your own at the campsite by—wait for it—filling an actual water bottle with hot water. Stick it inside a thick sock then stuff it in your bag. Just make sure the bottle is protected enough that you don’t risk scalding your skin. A hot drink before bed never hurts, either.

Kalee Thompson is a writer and editor whose favorite topics include natural disasters and maritime tragedies. She is the author of Deadliest Sea (HarperCollins, 2010) and her recent work has appeared in Popular Science, Matter, and The Hollywood Reporter. She lives in northeast Los Angeles with her husband and two little boys. Follow her on Twitter @kaleewrites.

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